A prospective study on the associations between dietary intakes of energy and macronutrients before menarche and age at menarche among girls

Based on the data from China Health and Nutrition Survey (CHNS), 840 girls aged 6-15 years who had information about menarche and participated in dietary survey at least once within 1-5 years before onset of menarche between 1989 and 2015 were included in the study. The median age at baseline of the 840 participants was 10 (9, 11) years. The median age at menarche of the participants was 13 (12, 14) years. After adjusting for the age of birth, place of residence, body mass index Z-score, physical activity level and annual household income per capita, the average age of menarche was advanced by 0.036 (95%CI: -0.068, -0.004) years for every 10 g increase in daily fat intake before menarche. The average age at menarche was 0.008 (95%CI: -0.014, -0.001) years earlier for every 1% increase in the daily energy supply ratio of fat before menarche.